In a typical lens removal procedure (i.e. a capsulotomy), the anterior portion of the lens bag that holds the crystalline lens of an eye is perforated to create a rhexis. The lens is then removed through the rhexis. In place of the removed lens, a prosthetic Intraocular Lens (IOL) is inserted into the lens bag. Two of the primary objectives of a lens removal procedure are that the implanted prosthetic IOL will function in the stead of the removed lens and that damage to the lens bag and other tissue in the eye will be substantially avoided, or at least minimized.
Heretofore, one method commonly used for removing the lens from its lens bag has involved phacoemulsification of the lens. In such a procedure, ultrasound waves break down lens tissue, and after the tissue has been sufficiently broken down it is aspirated. The intraocular lens (IOL) is then inserted into the lens bag.
Apart from phacoemulsification, it is also well known that lasers are very useful for altering lens tissue in the eye of a patient. More specifically, it is known that lens tissue can be effectively altered (i.e. photoablated) by a phenomenon that is widely referred to as Laser Induced Optical Breakdown (LIOB). An important result of LIOB is that very fine cuts through the tissue can be accomplished quickly. Moreover, these LIOB cuts can be made with great precision. A consequence of the ability of an LIOB procedure to cut into tissue is that due to the fineness of the cuts, and due to the ability to precisely control their placement, LIOB cuts can be made in compact patterns that will effectively pulverize lens tissue.
When performing a capsulotomy, it is clearly advantageous to accomplish the procedure as quickly as possible. This requirement then leads to a need for minimizing the time that is necessary to prepare the lens for removal. Actual removal of the lens tissue from the bag will then be dependent on the size and location of the rhexis that is used for the procedure.
In light of the above, it is an object of the present invention to provide a system and method for performing lens fragmentation with Laser Induced Optical Breakdown (LIOB) techniques that can be accomplished quickly, with great precision. Another object of the present invention is to effectively minimize the size of a rhexis that is required for the removal of a crystalline lens from its bag. Yet another object of the present invention is to provide a system and method for performing lens fragmentation which is simple to use, is easy to implement, and is relatively cost effective.